1. Field of the Invention
The present invention comprises a coded polymeric material identifiable by instrumental analytical techniques and to the method of identifying said material.
2. Description of the Prior Art
Polymeric materials, e.g., vinyl materials, comprise a selected polymer or polymers optionally combined with various functional additives (for example, lubricants, stabilizers, plasticizers, fillers, antioxidants, colorants, antistatic agents, flame retardants, processing aids, and/or the like). These polymeric materials can be formed into a final desired commercial product by the use of conventional forming procedures (for example, calendering, extrusion, compression molding, and the like). Quite often, these materials, at some point between the time of manufacture and ultimate acquisition by the user, will be devoid of any visible indicia (e.g., labels, tags, or the like) giving the identity of the manufacturer. If the goods are defective or do not conform to the desired performance specifications, it may be difficult to ascertain what manufacturer is responsible for suitable action in the event of deviation in the anticipated quality of the goods. Hence, a need exists for a means to code such goods, without placing visible indicia on the goods which can be removed therefrom, said coding means being quickly and easily detected and identifiable during any point in the commercial sales history of the goods.
In U.S. Pat. No. 3,912,928 to J. B. Rush et al., it is proposed that polymeric materials be coded with the incorporation in the material of a small amount of a particular phosphor so as to be identified at a later date. The process shown in this patent comprises the step of freshly exposing a surface of the coded material so that the phosphor particles can be bombarded with radiant energy to emit radiant energy which is visually identifiable by the human eye. Such a procedure involves the labor intensive step of freshly exposing a surface of the sample. The process also has the disadvantage of not being taught or suggested as being useful with instrumental methods of identification. Such instrumental methods can be more rapid, more accurate, and less labor intensive than the use of visual identification by the human eye.